Merge branch 'sphinx-doc' of https://github.com/termim/fio

[fio.git] / backend.c

diff --git a/backend.c b/backend.c
index 27e36bb0ae23e9cb1cf32c5c2840429edf6ebd5d..1c1f2f9a1e603c084160165eb6596945de344d7a 100644 (file)
--- a/backend.c
+++ b/backend.c
@@ -1261,6 +1261,10 @@ static int init_io_u(struct thread_data *td)
        return 0;
 }
 
+/*
+ * This function is Linux specific.
+ * FIO_HAVE_IOSCHED_SWITCH enabled currently means it's Linux.
+ */
 static int switch_ioscheduler(struct thread_data *td)
 {
 #ifdef FIO_HAVE_IOSCHED_SWITCH
@@ -1271,7 +1275,8 @@ static int switch_ioscheduler(struct thread_data *td)
        if (td_ioengine_flagged(td, FIO_DISKLESSIO))
                return 0;
 
-       sprintf(tmp, "%s/queue/scheduler", td->sysfs_root);
+       assert(td->files && td->files[0]);
+       sprintf(tmp, "%s/queue/scheduler", td->files[0]->du->sysfs_root);
 
        f = fopen(tmp, "r+");
        if (!f) {